一个与 (-) - - 斯巴尔泰因 - - Pd (II) 复合物的二次醇的分离选择性氧化中的结构和反应性相关的计算模型
Robert J Nielsen1, Jason M Keith, Brian M Stoltz
1Materials and Process Simulation Center, Beckman Institute (139-74), and The Arnold and Mabel Beckman Laboratories of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|June 24, 2004
概括
量子力学揭示了 (-) - - 斯帕特因-PdX(2) 复合体如何实现反选择性酒精氧化. 阳离子在介导固体相互作用中起着至关重要的作用,影响反应选择性和速率.
科学领域:
- 有机金属化学 有机金属化学
- 计算化学的计算化学
- 不对称的催化剂.
背景情况:
- (-) - - 斯帕特因-PdX(2) 复合物是二次醇对抗选择性氧化过程中的重要催化剂.
- 了解这些反应的机械复杂性是优化催化性能的关键.
研究的目的:
- 阐明控制由 (-) - - 斯巴尔泰因-PdX(2) 复合体催化二次醇的对抗选择性氧化的主要相互作用.
- 调查阴离子和溶剂在催化机制和选择性中的作用.
主要方法:
- 利用量子力学,特别是B3LYP密度函数理论 (DFT) 与PBF极化连续溶剂模型.
- 检查了多个反应路径和过渡状态,以确定反应机制.
主要成果:
- 确定了一种涉及酒精替代,脱,β-化物消除和产品释放的四步机制.
- 证明了离子对于传递连接体和基质之间的固体相互作用至关重要,决定了enantioselectivity.
- 证明溶剂介电性质通过影响离子金属相互作用影响反应速率和选择性.
结论:
- 离子的存在及其与中心的相互作用对于在 (-) - - 斯巴铁因-PdX(2) 催化氧化过程中实现选择性至关重要.
- 溶剂效应显著调节催化活性和立体化学结果.
- 计算模型根据计算过渡状态能量准确预测观察到的enantioselectivities.
相关概念视频
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